[streetrodderbn]

After a head and cam change on my son's 355 Chevy, I encountered the problem with a swapmeet intake manifold that has obviously been milled. The intake will bolt on without an intake gasket, but you cannot bolt it on with a gasket, the bolt holes are too high to start the bolts on each side(the intake bolt threads are lower than the holes in the intake.)I tried another intake manifold, with a gasket, and it bolted up fine. Can I correct the milling on the swapmeet intake, or should I just buy another one?

[hcompton]

If the intake was milled it would be smaller not larger right? I could see it being cut back but dont know why itwould be to tight a fit with the gaskets. Is the top and bottom of the intake plate have the same amount of gap.

Correct gaskets does the intake have egr. Have you tried a cheap thin gasket? Or trim the gaskets back at the bottom and see if they are fitting.

Have the heads been angle milled or regular resufacing? Also was the block decked. Sometimes this will cause fitment issues. A die grinder will usally correct that issue.

[hcompton]

If the block has been decked and easy way to figure out how much needs to come off the bottom rail of the intake is to bolt the intake up with one gasket and then see what the difference is on the other side. Gaskets are .060 so if one gasket on one head give almost no room on the other side then you will need to take .030 off each side of the manifold and then normal gaskets will work.

This can also be done with a die grinder but maybe not the best way to handle the problem. Is this a victor manifold they do fit really tight. Newer manifolds have a wee bit more room since a lot of blocks are decked these days but the victor and other race style manifolds may still be really tight.

If it almsot fits you can use thinner gaskets cometic i think will make any size you want but may result in a poor seal. I usally like to have felpro print o seals in the intake manifolds.

[timothale]

A long time ago I had a chart that showed how much to mill, It depends on the machine work done to the heads and block, the percentages depended on the intake to head centerline angle vs the other dimensions centerlines, It is different % for different engines, that was done to get the bolt holes to line up. Then you needed to match the ports to the heads.

[sqzbox]

Originally Posted by streetrodderbn

After a head and cam change on my son's 355 Chevy, I encountered the problem with a swapmeet intake manifold that has obviously been milled. The intake will bolt on without an intake gasket, but you cannot bolt it on with a gasket, the bolt holes are too high to start the bolts on each side(the intake bolt threads are lower than the holes in the intake.)I tried another intake manifold, with a gasket, and it bolted up fine. Can I correct the milling on the swapmeet intake, or should I just buy another one?

Buy another one. rigging the milled one will cause other problems like oil coming out around the intake bolts.

[Richiehd]

Originally Posted by sqzbox

Buy another one. rigging the milled one will cause other problems like oil coming out around the intake bolts.

Agreed, and you might have to shim distributer too.

[streetrodderbn]

Thats what i figured ! I tried the previous intake on the new heads, with the same gasket, it bolted up fine, But it's the wrong intake for this combination.

[hcompton]

Originally Posted by streetrodderbn

Thats what i figured ! I tried the previous intake on the new heads, with the same gasket, it bolted up fine, But it's the wrong intake for this combination.

If the block or heads have been cut you will have issues and should check the distributer clearnce just to be sure.

Intake are usally cheap to have cut. I would either touch it up my self or have the right one cut to fit. Its usally only a little bit Of metal needs to come off so a file can complete the job if all else fails.

[streetrodderbn]

the block is the same, I just replaced the cylinder heads,cam and intake. The engine only has @200mi since fresh rebuild. We are just upgrading the horsepower. I still don't understand why the intake sits soo high. After inspection, even the original intake that will bolt up) sits high, Could this be from the heads being angle milled? with no gasket, the intake sits flush on all 4 sides, and the threads are centered within the intake bolt holes.

[streetrodderbn]

Solved the problem with a new Edelbrock Performer R.P.M.! anybody want to buy a slightly used intake/Chunk of aluminum to melt down???LOL